Biaxial loading and shallow-flaw effects on crack-tip constraint and fracture-toughness

Conference · Wed Dec 01 04:00:00 EST 1993

OSTI ID:10105930

Pennell, W E; Bass, B R; Bryson, J W; McAfee, W J; Theiss, T J; Rao, M C

Uniaxial tests of single-edged notched bend (SENB) specimens with both deep- and shallow-flaws have shown elevated fracture-toughness for the shallow flaws. The elevation in fracture-toughness for shallow flaws has been shown to be the result of reduced constraint at the crack-tip. Biaxial loading has the potential to increase constraint at the crack-tip and thereby reduce some of the shallow-flaw, fracture-toughness elevation. Biaxial fracture-toughness tests have shown that the shallow-flaw, fracture-toughness elevation is reduced but not eliminated by biaxial loading. Dual-parameter, fracture-toughness correlations have been proposed to reflect the effect of crack-tip constraint on fracture-toughness. Test results from the uniaxial and biaxial tests were analyzed using the dual-parameter technology. Discrepancies between analysis results and cleavage initiation site data from fractographic examinations indicate that the analysis models are in need of further refinement. Addition of a precleavage, ductile-tearing element to the analysis model has the potential to resolve the noted discrepancies.

• Research Organization: Oak Ridge National Lab., TN (United States)
• Sponsoring Organization: Nuclear Regulatory Commission, Washington, DC (United States)
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 10105930
• Report Number(s): CONF-931079--13; ON: DE94003496
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
220200
COMPONENTS AND ACCESSORIES
CRACKS
DEFECTS
FRACTURE MECHANICS
FRACTURE PROPERTIES
PRESSURE VESSELS